Improvement in hot-blast pipes



w. B. POLLOCKL Hqt Blast Pipe. Patented March 7, 1865.

I Witnesses:

VLAMJM Units STATES WM. B. POLLOOK, OF YOUNGSTOWN, OHIO.

IMPROVEMENT IN HOT-BLAST PIPES.

Specification forming part of Letters Patent No. 6,698, dated March 7, 1565.

T0 00% whom it may concern:

Be it known that 1, WILLIAM B. PoLLooK, of Youngstown, in the county ofMahoning and State of Ohio, have invented a new and useful Improvementin Hot-Blast Pipes for Furnaces, of which the following is a full,clear, and exact description, reference being had to the accompanyingdrawings, which make a part of this specification, and in which- Figure1 is a view in perspective showing part of my invention in open, andpart in closed, pipes, with a portion of the furnace wall. Fig. 2 is avertical section through one of the pipes, and Fig. 3 .a section throughthe trunks on which the pipes rest and the pipe connecting the trunks.

It is the object of my invention to conduct the hot air forblast-furnaces over a large surface of the heated portions of the stackwithout extending the pipes to an inconvenient length, under anarrangement that shall admit of easy access to the interior of anyportion of the pipes for the purposes of cleansing or repair, withoutstopping the furnace, and to establish a uniform expansion throughouteach of the pipes; and to these ends my improvement consists, first, inplacing a diaphragm through the trunks and the pipes resting thereon, soas to compel the air to ascend in one half and descend on the oppositehalf of each pipe, and thus double the heating-surface withoutincreasing the length of the pipes;

secondly, in connecting the section-pipes at the bottom to the trunks bya slip-joint, and at the top by a clasp or bolt, so as to admit of theremoval of one or more sections without stopping the furnace and withonly a short interruption to the blast; thirdly, in making the pipes insections and uniting them in the center of their length, (but withouttheir having. any communication directly with each other,) so that eachpair of sections constituting a single pipe will have equal expansion,and the varying expansion of the pipes differently located will notfracture or injure one another.

My system of pipes may be arranged to suit any desired form or size ofblast-furnace, and

may be located within the brick-work or against it, (as at A, Fig. 1,)in which latter position it is obvious that the products of combustionescaping from the furnace will pass on 7 both. sides of and between thepipes; or an independent fire may be used with my system of pipes,whiclrcan be located wherever desired.

I construct two trunks, B B,'of any sufficiently refractory metal tosustain the heat of the spot in the furnace in which they are located,as a base for the pipes C. These trunks are closed at their rear end,but are connected together by a coupling-pipe, D, having aflange on eachend-to match the flanges on the short pipes E E on the trunks. The frontend of the trunk 13 has an opening, I), terminating in a flange, c, towhich the pipe terminating at the tuyere is to be united, while thefront end of trunk B has an opening terminated by the flange c toreceive a pipe from the blast-gen erator. The position of these openingscan, however, bechanged at pleasure to adapt them most advantageously,and it is indifferent at which end of the trunk the blast may be introduced. On the top of the trunks short pipes F are placed, equal innumber to the number of pipes to be used. These short pipes must beplaced on a line through their centers and through the centers of thetrunks, and directly opposite each other on both trunks, as seen inFigs. 1 and 2. On these trunks the pipes O are placed, and may be of anylength required to give the temperature of the blast desired. The pipesO are made in sections divided in the center of their length, at whichpoint each section is closed.- by an air-tight cap, (Z, that may carry aprojecting lip, e, by which means the two opposite sections of each pipecan be secured together by bolts passing through the lips or by a ringslipped over them, while the sections at their lower end rest on thetrunks fitting neatly around the short pipes F. The trunks B B and shortpipes F are divided centrally and longitudinally by avertical diaphragm,G, which passes from the bottom of the trunks to the top of the severalshort pipes F, so as effectually to prevent the passage of the blastthrough them in any other directions than those shown by the red arrowsin Figs. 2 and 3. The sections of the pipes O are likewise dividedvertically and longitudinally by diaphragms H,that register truly withthose G of the short pipes F at the lower end of the sections, so as tomake the diaphragms continuous from the bottom of the trunks to near theupper ends of the sections, where they terminate, as shown at I h, Fig.2, leaving the sections of their full I changes obviously would notinduce the necesdiameter for the length of one diameter, at least, as atz, Fig. 2. The trunks B B being placed in position, the sectional pipes0 put over the short pipes F, and secured by passing a ring over orbolts through the lips e, the connecting-pipe D fastened to the trunksby its flanges, and the induction and eduction properly attached, theblast may be introduced; when it will enter the trunk B, ascend theright half of the pipes 0, pass around the end of the diaphragm h, downthe left side of the pipes O, (as shown by the red arrows, Fig. 2,)through the connecting-pipe D, (as similarly shown in Fig. 3,) up theright half of the opposite sections of the pipes 0, around the diaphragmh down the left side of the pipes O, and through the escape-pipe to thetuyere. The blast having thus traversed through the pipes this distance,double their length and that of the trunks, while both were acted uponover nearly their entire surface by the heated products of combustionescaping from the furnace, will have attained thedegree of heat requiredfor the most effective results in the rapid reduction of ores to theirmetals.

Should one of the pipes or sections become burned or fractured, it isobvious that it can easily be removed and repaired or replacedby a newone simply by lifting it out of place and covering or closingthe shortpipe on which the injured section rested with an air-tight cap, to beremoved when the repaired or new pipe is restored. The stoppage of theblast for the brief period required to makathese sity for stopping thefurnace. It islikewise evident that these pipes, differently situated inthe series, may have varying degrees of expansion or contraction withoutinjury to each other.

For example, the pipe situated in the least heated locality in the stackwill be unaffected by the greater expansion of the pipe that is morehighly heated. I

What I claim as my invention in hot-blast pipes of furnaces, and desireto secure by Letters Patent of the United States, is:

1. The combination of the trunks B B with the sectional pipes C andconnecting-pipe D, arranged substantially in the manner and for thepurpose set forth.

2. The combination of the trunks, diaphragms, and section-pipes,substantially in the manner described, so that an injured or worn tubeor section may be singly removed and a new one inserted without stoppingthe blast longer than merely to make the removal or change of thesection.

3. Making the continuous pipes in sections, and so uniting them with thetrunks that any one of the several pipes may expand unequally andindependently with out fracturing the others having a differentexpansion, as set forth.

In testimony whereof I have hereunto subscribed my name.

WVM. B. POLLOOK.

WVitnesses:

PAUL J oNEs, GEo. J. MARGERUM.

